Perfluorodiglycidyl ethers

ABSTRACT

Perfluoroglycidyl ethers of the formula  &lt;IMAGE&gt;  are prepared by epoxidation of a perfluorodiallyl ether of the formula: CF2=CFCF2ORF.

TECHNICAL FIELD

This invention relates to perfluorodiglycidyl ethers, their preparationand polymers therefrom.

BACKGROUND ART

P. Tarrant, C. G. Allison, K. P. Barthold and E. C. Stump, Jr.,"Fluorine Chemistry Reviews", Vol. 5, P. Tarrant, Ed., Dekker, New York,New York (1971) p 77 disclose fluorinated epoxides of the generalformula: ##STR2## wherein R_(F) may be a perfluoroalkyl group of up to10 carbons containing one or more functional substituents: ##STR3##

Oxidations of the type ##STR4## are disclosed where X is --F, --(CF₂)₅ H(U.S. Pat. No. 3,358,003), --CF₂ Cl or --CF₂ Br (T. I. Ito et al,Abstracts, Div. Fluoro. Chem., Am. Chem. Soc., 1st ACS/CJS Chem.Congress, Honolulu, HI, April 1979)

Oligomers and polymers of perfluoroepoxides ##STR5## are described inU.S. Pat. No. 3,419,610 and by P. Tarrant et al. in Fluorine Chem.Reviews, 5, pp 96-102 (1971). Nonfunctional fluoroethers ofdifluoroacetyl fluoride of the formula R_(F) OCF₂ COF are also known,and the insertion of one or more moles of hexafluoropropene epoxide intosaid nonfunctional perfluoroethers is disclosed in U.S. Pat. No.3,250,808: ##STR6## where n is 1 to at least 6 and R_(F) isperfluoroalkyl, perfluoroalkoxy, or perfluoroalkoxyalkyl.

Glycidyl ethers containing the segment ##STR7## are widely disclosed.The glycidyl ##STR8## is disclosed in U.S. Pat. No. 4,127,615.

DISCLOSURE OF INVENTION

Novel perfluoroglycidyl ethers are provided having the general formula:##STR9## wherein R_(F) is: ##STR10## wherein R¹ is a carbon-carbon bondor a linear or branched perfluoroalkylene group of 1 to 12 carbon atoms;##STR11## Y and Y' are --F or --CF₃, provided that only one of Y and Y'can be --CF₃ ; or: ##STR12## wherein R³ is a linear or branchedperfluoroalkylene group of carbon content such that the moiety ##STR13##does not exceed 15 carbon atoms; Y independently is --F or --CF₃ ; n is1 to 4; and Q is as defined above. Ethers of formula I where Q is --OCF₂CF═CF₂ are useful as intermediates in the preparation of thecorresponding perfluorodiglycidyl ether.

Perfluoroglycidyl ethers of formula I are prepared by contacting andreacting the corresponding perfluorodiallyl ethers with oxygen.

The ethers of formula I may be homopolymerized, or copolymerized withsuitable fluorinated epoxides which include hexafluoropropene oxide,tetrafluoroethylene oxide, and other perfluorodiglycidyl ethers offormula I.

Polymers prepared from formula I glycidyl ethers provide crosslinking orcure sites and are stable elastomeric materials useful as sealants,caulks, and fabricated objects. Preferred are ethers of formula I whereR_(F) is: ##STR14##

Perfluorodiallyl ethers, when reacted with O₂, also yield, in additionto the perfluorodiglycidyl ethers of formula I, coproduct fluoroformyldifluoromethyl ethers containing one less carbon atom which have thegeneral formula: ##STR15## wherein R_(F) is as defined above.

The novel perfluoroglycidyl ethers of this invention are prepared fromthe perfluorodiallyl ethers which are disclosed by Krespan in U.S.application Ser. No. 145,756, filed May 1, 1980 now U.S. Pat. No.4,275,225, issued June 23, 1981. These perfluorodiallyl ethers are ofthe formula:

    CF.sub.2 ═CFCF.sub.2 OR.sub.F '

wherein R_(F) ' is: ##STR16## wherein R¹ is a carbon-carbon bond or alinear or branched perfluoroalkylene group of 1 to 12 carbon atoms; Q¹is --OCF₂ CF═CF₂ ; Y and Y' are --F or --CF₃, provided that only one ofthe Y and Y' can be --CF₃ ; or ##STR17## wherein R³ is a linear orbranched perfluoroalkylene group of carbon content such that the moiety##STR18## does not exceed 15 carbon atoms; Y is --F or --CF₃ ; n is 1 to4; and Q¹ is as defined above.

The perfluoroglycidyl ethers of this invention are also prepared fromperfluorodiallyl ethers of the formula: ##STR19## wherein R³, Q¹, and nare as defined under (ii) above, and Y, independently, can be --F or--CF₃.

These perfluorodiallyl ethers are prepared by

(1) mixing and reacting:

(a) a carbonyl compound having the formula: ##STR20## wherein A¹ is##STR21## where R¹ is a carbon-carbon bond or a linear or branchedperfluoroalkylene group of 1 to 12 carbon atoms; Q' is --OCF₂ CF═CF₂ ; Yand Y' are --F or --CF₃, provided that only one of Y and Y' can be --CF₃; or

(b) a carbonyl compound having the formula: ##STR22## wherein A² is##STR23## where R³ is a linear or branched perfluoroalkylene group ofcarbon content such that the moiety ##STR24## does not exceed 14 carbonatoms; Y independently is --F or --CF₃ ; n is 1 to 4; and Q' is definedas above; with a metal fluoride of the formula MF where M is K-, Rb-,Cs-, or R₄ N- where each --R, alike or different, is alkyl of 1 to 6carbon atoms; and

(2) mixing the mixture from (1) with a perfluoroallyl compound of theformula:

    CF.sub.2 ═CF--CF.sub.2 Z

wherein:

    Z is --Cl, --Br or --OSO.sub.2 F.

The perfluoroglycidyl ethers of formula I and the fluoroformyldifluoromethyl ethers of formula II are prepared from theperfluorodiallyl ethers by partial or complete reaction with oxygen atabout 20° to about 200° C., preferably about 80° to about 160° C.:##STR25## where x and y are, respectively, the mole fractions ofproducts I and II, and R_(F) and R_(F) ' are defined as above. Ethers offormula I are normally stable at the reaction temperature. Formation ofethers of formula II, together with carbonyl fluoride, is presumed toresult from oxidative cleavage of an allylic double bond in the startingperfluorodiallyl ether. The by-product COF₂ is normally inert.

The epoxidation reaction may be carried out at pressures of about 5 toabout 3000 psi, preferably about 50 to about 1500 psi. Solvents are notessential, but inert diluents such as1,1,2-trichloro-1,2,2-trifluoroethane (CFCl₂ CF₂ Cl) orperfluorodimethylcyclobutane may be used.

Reactant proportions may vary from a large molar excess of olefin overO₂ (e.g., 100:1) to a large excess of O₂ over olefin (e.g., 100:1); amodest excess of O₂, e.g., about 1.1:1 to about 10:1, is normallypreferred to insure complete reaction of the olefin. When preparing aperfluoroglycidyl ether of formula I wherein Q is --OCF₂ CF═CF₂, thereaction of the starting diolefin with O₂ should be run with at least a2:1 molar excess of diolefin over O₂, and further addition of O₂ shouldbe avoided.

The epoxidation reaction is most conveniently initiated thermally, butmay be catalyzed by the use of free-radical initiators or by ultravioletirradiation in the presence of a photoactive material such as bromine.The epoxidation may be conducted in a batchwise or continuous manner.

The epoxidation product of formula I is generally isolated by directfractional distillation, although in some cases a preliminary treatmentwith Br₂ or Cl₂ may be helpful. When epoxidation is carried out at lowertemperatures (100°), addition of radical acceptors such aso-dichlorobenzene to the mixture just prior to fractionation is adesirable precaution against the possible presence of peroxides.

Perfluoroglycidyl ethers of formula I can be homopolymerized orcopolymerized with suitable fluorinated epoxides such as HFPO,tetrafluoroethylene epoxide (TFEO), other perfluoroglycidyl ethers offormula I and perfluoroglycidyl ethers disclosed in copending U.S.Patent Application Ser. No. 250,906, filed simultaneously herewith byKing et al.; HFPO and TFEO are preferred comonomers with HFPO mostpreferred. (Co)-polymerization proceeds in the presence of a suitablesolvent and initiator at temperatures of about -45° to about +25° C.,preferably about -35° to about 0° C. The quantity of solvent may be fromabout 5 to about 40 mole percent of the total monomer feed. Suitablesolvents include commercial ethers such as diethyl ether, diglyme,triglyme and tetraglyme (di-, tri-, and tetraethyleneglycol dimethylether), and fluorinated solvents such as 1,1,2-trichlorotrifluoroethane,chlorotrifluoroethylene, dichlorodifluoromethane, hydrogen-capped HFPOoligomers of the formula CF₃ CF₂ CF₂ O[CF(CF₃)CF₂ O]_(n) CHFCF₃, where nis 1 to 6, dimers and trimers of hexafluoropropene (HFP), and HFPitself; the latter is a preferred solvent. Solvents should be thoroughlydried, preferably by means of molecular sieves, before use.

Catalysts suitable for the (co)polymerization of formula I ethersinclude anionic initiators which are effective for the polymerization ofhexafluoropropylene oxide (HFPO), such as carbon black or, preferably,combinations CsF-LiBr, KF-LiBr, (C₆ H₅)₃ PCH₃, -LiBr, CsF-FOCCF(CF₃)OCF₂CF₂ OCF(CF₃)COF, CsF-CF₃ CF₂ CF₂ O[CF(CF₃)CF₂ O]_(n) CF(CF₃)COF, where nis 2 to 6; the latter catalyst wherein n is 4 to 6 is preferred.Preparation of fluoropolyethers such as that used in the last mentionedcatalyst is described in U.S. Pat. No. 3,322,326. Catalyst concentrationshould be about 0.05 to about 1 mole percent of the total monomer feedwhen higher molecular weight products are desired.

The perfluoroglycidyl ethers of formula I and comonomers such as HFPOshould be reasonably pure and dry before (co)polymerization. Monomersmay be dried with molecular sieves or, preferably, over KOH-CaH₂.Dryness and high purity are necessary for the preparation of highmolecular weight (co)polymers from formula I ethers.

Polymerization pressures may be in the range of from less than oneatmosphere to about 20 atmospheres or more; pressures in the vicinity ofone atmosphere are normally preferred.

The copolymerization of the perfluoroglycidyl ethers of formula I withHFPO, TFEO and other perfluoroglycidyl ethers can be a randomcopolymerization whereby the various monomers are added and reacted withone another simultaneously, or the copolymerization can be sequential,i.e., the perfluorodiglycidyl ethers of formula I wherein Q is ##STR26##can be subsequently copolymerized with material previously polymerized,such as hexafluoropropylene oxide homopolymers as disclosed in copendingU.S. Patent Application Ser. No. 250,905 filed simultaneously herewithby Darling and hexafluoropropylene oxide/perfluoroglycidyl ethercopolymers as disclosed in copending U.S. Patent Application Ser. No.250,906 filed simultaneously herewith by Krespan et al. Such asequential copolymerization can serve as a specialized form of chainextension.

In the following examples of specific embodiments of the presentinvention, parts and percentages are by weight and all temperatures arein degrees C. unless otherwise specified. The most preferred polymer ofthe present invention is that of Example 9.

EXAMPLE 1 Perfluoro-1,2-epoxy-13,14-epoxy-4,11-dioxatetradecane andPerfluoro-12,13-epoxy-3,10-dioxatridecanoyl Fluoride ##STR27##

A sample of perfluoro-4,11-dioxatetradeca-1,13-diene (51.7 g, 0.087 mol,purified by distillation from conc. H₂ SO₄) was diluted to 75 ml withdry CFCl₂ CF₂ Cl, loaded into a 100-ml stainless steel tube and heatedat 140° while O₂ was injected in 50 psi increments. The maximum pressurewas 500 psi, at which point O₂ consumption ceased as judged by lack ofpressure drop. Distillation of the liquid products gave 39.1 g offractions with bp 56° (95 mm)-81° (8.0 mm). Analysis by gc revealed asingle major peak for all fractions with a total of 5-15% of varyingimpurities present. However, IR and NMR showed that this main peakrepresented both products. An early fraction, 6.4 g, bp 62°-64° (9 mm),was nearly pure perfluoro-12,13-epoxy-3,10-dioxatridecanoyl fluoride. IR(CFCl₂ CF₂ Cl): 5.28 (COF), 6.59 (epoxide), 7.5-9.5μ (CF, C--O). NMR(CCl₄ /CFCl₃): ¹⁹ F 13.1 (m, 1F, COF), -77.2 (t of d, J_(FF) 11.6, 2.5Hz, 2F, CF₂ COF), -83.3 (m, 4F, CF₂ O), -122.5 (m, 4F, CF₂), -125.8 (m,4F, CF₂), and -156.7 ppm (t, J_(FF) 18 Hz, 1F, CF) with AB groupings forring CF₂ at -103,901 and -10,433 Hz (d of t, J_(FF) 18.8, 9.6 Hz, 1F)and -10,617 and -10,659 Hz (d, J_(FF) 17.4 Hz, 1F), and for CF₂ adjacentto epoxide ring at -7369, -7523, -7553, and -7706 Hz (m, 2F).

Higher-boiling cuts, 21.8 g, bp mainly 68°-70° (8 mm), contained chieflydiepoxide with epoxyacid fluoride as a major impurity. These higher cutswere combined and shaken with 200 ml of cold water for 5 min. Heat ofreaction, cloudiness and some foaming were apparent. A portion of thelower layer was dried over anhydrous CaSO₄. It was then transferredtrap-to-trap twice under vacuum to give 4.26 g of clear colorlessperfluoro-1,2-epoxy-13,14-epoxy-4,11-dioxatetradecane, 99% pure by gc.IR (neat): 6.59 (epoxide) and 7.5-9.5μ (CF, C--O) with no bands for OH,C═O, or C═C detected. NMR (CCl₄ /CFCl₃): ¹⁹ F -83.5 (m, 4F, CF₂ O),-122.7 (m, 4F, CF₂), -125.9 (m, 4F, CF₂), and -156.9 ppm (t, J_(FF) 18Hz, 2F, CF) with AB groupings for ring CF₂ at -10391 and -10658 Hz (d,J_(FF) 17.4 Hz, 2F) and for CF₂ adjacent to epoxide ring at -7378,-7531, -7561, and -7714 Hz (m, 4F) with only trace impurities present.

Anal. Calcd for C₁₂ F₂₂ O₄ : C, 23.02. Found: C, 23.68.

It is considered probable that the epoxidation reaction proceeded viathe allyloxy-epoxide intermediate ##STR28##

EXAMPLE 2Perfluoro(1,2-epoxy-15,16-epoxy-6,11-dimethyl-4,7,10,13-tetraoxahexadecane)##STR29##

A suspension of 20.3 g (0.35 mol) of flame-dried KF in 300 ml of drydiglyme while stirred at 0°-5° while 53.0 g (0.125 mol) ofperfluoro(2,7-dimethyl-3,6-dioxasuberoyl) fluoride was added. Themixture was stirred for 30 min, after which 80.5 g (0.35 mol) ofperfluoroallyl fluorosulfate was added at 0°-5°. After having stirredfor 3 hr at 0°-5°, then at 25° for 2 hr, the mixture was poured into 1 lof cold water. The lower layer was washed with 500 ml of water, driedover CaSO₄ and fractionated to afford 47.3 g (52% ) of pureperfluoro(6,11-dimethyl-4,7,10,13-tetraoxahexadeca-1,15-diene). IR(neat): 5.58 (C═C), 8-9μ (CF, C--O). NMR (CCl₄ /CFCCl₃): ¹⁹ F -72.1 (dof t of d of d, J_(FF) 24.7, ˜13.7, 13.7, 7.3 Hz, 4F, OCF₂ C═), -80.7(m, 6F, CF₃), -84.1 (m, 4F, OCF₂), -92.1 (d of d of t, J_(FF) 52.6,39.4, 7.3 Hz, 2F, cis-CF₂ CF═CFF), -105.5 (d of d of t, J_(FF) 118.0,52.6, 24.7 Hz, 2F, trans-CF₂ CF═CFF), -146.0 (t, J_(FF) 21.3 Hz, 2F,CF), and -190.9 ppm (d of d of t, J_(FF) 118.0, 39.4, 13.7 Hz, 2F, -CF₂CF═CF₂), with an AB pattern for OCF₂ at -7988, -8122, -8142, and -8258Hz (m, 4F).

Anal. Calcd. for C₁₄ F₂₆ O₄ : C, 23.15. Found: C, 23.29. ##STR30##

A solution of 45.7 g (0.063 mol) of the above hexadecadiene in 75 ml ofCFCl₂ CF₂ Cl was heated at 140° in a 100-ml stainless steel-lined tubewhile oxygen was injected portionwise until reaction was complete.Distillation of the liquid product afforded 37.2 g of fractions with bp63° (10 mm)-65° (4 mm) shown by IR and NMR to beperfluoro(1,2-epoxy-15,16-epoxy-6,11-dimethyl-4,7,10,13-tetraoxahexadecanecontainingperfluoro(14,15-epoxy-5,10-dimethyl-3,6,9,12-tetraoxapentadecanoyl)fluoride as the major impurity. Several fractions (22.7 g) was combinedand contacted with CaH₂ while standing open to atmospheric moisture fora day. The open mixture was then stirred for 4 hr and filtered.Volatiles were transferred at 50° (0.05 mm), stirred with CaSO₄ for 2hrs, and then transferred again at 45° (0.05 mm) to give 5.5 g of nearlypure diepoxide. IR (neat): 6.47 (epoxide) and 8- 9μ (CF, C--O) with veryweak impurity bands present at 5.28 (COF) and 6.64 (CO₂ H).

Other fractions were shown by ¹⁹ F NMR to contain about 8.2 g ofdiepoxide as 80% pure material, for a total of 13.7 g (29%).

EXAMPLE 3 Perfluoro(1,2-epoxy-10,11-epoxy-4,8-dioxaundecane) ##STR31##

A 100-ml metal tube containing 107 g (0.24 mol) ofperfluoro(4,8-dioxa-1,10-undecadiene) was heated at 140° while oxygenwas injected portionwise until reaction was nearly complete.Fractionation of the liquid products gave 66.7 g, bp 42°-64° (50 mm),containing mainly diepoxide and epoxyacid fluoride. This distillate wasirradiated with excess bromine to remove any olefinic material, residualbromine was evaporated, and the residue was shaken with a mixture of 250ml of ice water and 50 ml of CFCl₂ CF₂ Cl. The organic layer was driedover CaSO₄ and distilled to give 27.5 g of nearly pure diepoxide, bp60°-68° (100 mm). The distillate was treated with CaSO₄, filtered andredistilled to give 19.6 g (17%) of pure diepoxide, bp 54°-56° (50 mm).IR (CCl₄ /CFCl₂ CF₂ Cl): 6.49 (epoxide), 8-9μ (CF, (C--O). NMR (CCl₄/CFCl₃): ¹⁹ F -84.2 (m, 4F, OCF₂), -130.1 (s, 2F, CF₂), and -157.1 ppm(t, J_(FF) 17.5 Hz, 2F, CF) with AB patterns for CF₂ adjacent to epoxidering at -7399, -7550, -7594, and -7747 Hz (m, 4F) and for ring CF₂ at-10415 and -10,457 (d of t, J_(FF) 18.7, 9.7 Hz, 2F) and -10,643 and-10,684 Hz (d, J_(FF) 16.4 Hz, 2F).

Anal. Calcd. for C₉ F₁₆ O₄ : C, 22.71; F, 63.85. Found: C, 22.99; F,63.92.

EXAMPLE 4 Copolymerization ofPerfluoro(1,2-epoxy-15,16-epoxy-6,11-dimethyl-4,7,10,13-tetraoxahexadecane)with Hexafluoropropylene Oxide

The polymerization catalyst was prepared by reacting 2.09 g (0.0137 mol)CsF, 6.07 g (0.0273 mol) tetraglyme and 7.97 g (0.0120 mol) HFPOtetramer. The catalyst was shaken for at least 6 h and centrifuged for30 min at 0°. To a thoroughly dried 4-neck 500-ml flask was injected 4millimole of the prepared catalyst. The reaction mixture was then cooledto -35° C. Hexafluoropropylene (dried by passing through molecularsieves) was added at a rate of 1 g/min for a total of 20 g.

4.97 g of the diepoxide of Example 1 and 144 g of HFPO (dried by passingover KOH and CaH₂) were copolymerized over a period of 35.3 hr at -34°to -35°. After this period, the stirring was extremely difficult due tothe almost semisolid condition of the polymer. Part of the recoveredpolymer, 15 g, was reacted with 10% NaOH in ethyl carbitol to a neutralpoint with phenolphthalein indicator. The sodium salt was decarboxylatedby heating to 160° for 30 min. The isolated polymer gave ηinh of 0.195in Freon® E3 ##STR32## The calculated molecular weight is 200,000. Basedon the 3.34% by weight of added diepoxide, the ratio of HFPO units todiglycidyl monomer units is approximately 132:1.

EXAMPLE 5 Terpolymerization ofPerfluoro(1,2-epoxy-15,16-epoxy-6,11-dimethyl-4,7,10,13-tetraoxahexadecane)and Perfluoro-6,7-epoxy-4-oxaheptanenitrile with HexafluoropropyleneOxide

Two monomers were combined as follows: 2 g of the diepoxide of Example 1were mixed with 4.67 g of the epoxynitrile. Following the procedure forHFPO copolymerization (Example 4), 6.34 g of the mixed monomers and 177g of HFPO were copolymerized at -33° to -35° over a period of 42.3 hr.The molecular weight by inherent viscosity was 41,000. On standing atroom temperature over a period of 31/2 months, there was further curingof the polymer resulting in a partially solidified material. From theweight % added monomers the ratio of HFPO units to nitrile monomer unitsto diglycidyl monomer units is approximately 431:8:1.

EXAMPLE 6 Curing of Terpolymer ofPerfluoro(1,2-epoxy-15,16-epoxy-6,11-dimethyl-4,7,10-13-tetraoxahexadecane),Perfluoro-6,7-epoxy-4-oxaheptanenitrile and Hexafluoropropylene Oxide

The following was milled until a homogeneous mix was obtained: 5.46 g ofthe terpolymer of Example 5, 0.55 g carbon black, 0.16 g tetraphenyltinand 0.16 g magnesium oxide. The milled material was degassed by placingin a vacuum oven for 16 hr at 50°. This was then placed in amicrotensile bar mold and pressed in a Carver press under 500 psi at210° for 4 hr. At this point a soft rubbery tensile bar was obtained.

EXAMPLE 7 Copolymerization ofPerfluoro(1,2-epoxy-10,11-epoxy-4,8-dioxaundecane) withHexafluoropropylene Oxide

Following the procedure for HFPO copolymerization (Example 4), 5.78 g ofthe diepoxide of Example 3 and 165 g of HFPO were copolymerized over aperiod of 51.1 h at -34° to -36°. The molecular weight by IR was 16,000.The ratio of HFPO units to diglycidyl monomer units is approximately82:1. On standing at room temperature for 3 weeks, there was a visibleincrease in viscosity.

EXAMPLE 8 Copolymerization of Perfluoro-6,7-epoxy-4-oxaheptanenitrilewith Hexafluoropropylene Oxide

The polymerization vessel consisted of a fully glass jacketed four-neckround bottom reactor which is equipped with a paddle stirrer, Dry Icereflux condenser, gas inlet port and a thermocouple well. The entirereactor was dried thoroughly at 200° C. in a dry nitrogen atmosphere andwas assembled and kept dry with a blanket of high purity dry nitrogen.Methanol was used as a coolant and was pumped through the coolant jacketfrom a Neslab ULT80 low temperature circulator and refrigerator system.Initiator was prepared by adding, under dry nitrogen, 7.95 grams (7.8milliliters, 0.0358 mole) of tetraglyme to 2.54 grams (0.0167 mole) ofcesium fluoride and then adding 2.91 grams (1.75 ml, 0.0068 mole) of2,2'-[(tetrafluoroethylene)dioxy]bis-(tetrafluoropropionyl fluoride).The mixture was shaken overnight at room temperature and thencentrifuged for 30 minutes to remove unreacted cesium fluoride. With thereactor at room temperature 4 milliliters of initiator was introduced bymeans of syringe and the reactor was cooled to an internal temperatureof between -30° to -34° C. Liquified hexafluoropropylene was used as asolvent to dilute the cold viscous initiator solution. Thepolymerization was carried out at -34° C. using the following monomersand diluent addition schedule. The approximate addition rates were 0.126g/hr for perfluoro-6,7-epoxy-4-oxaheptanenitrile and 5.7 g/hr forhexafluoropropylene oxide which was purified in a two-stage (potassiumhydroxide/calcium hydride) scrubber and was added as a gas in semi-batchfashion.

    ______________________________________                                        Addition  HFP          Curesite   HFPO                                        Time (hrs)                                                                              Diluent (g)  Monomer (g)                                                                              (g)                                         ______________________________________                                        0.23       7           0          0                                           2.67                   0          15.2                                        10.3                   1.29       58.7                                        2.0       30                                                                  23.0                   2.90       131.0                                       2.0       30                                                                  22.25                  2.80       126.8                                       Total     67           6.99       331.7                                       ______________________________________                                    

EXAMPLE 9 Subsequent Copolymerization withPerfluoro-1,2-epoxy-13,14-epoxy-4,11-dioxatetradecane

30 grams of hexafluoropropylene (HFP) were added to the product ofExample 8 to reduce viscosity and improve mixing of the polymer mass.Then a solution of 1.9 g of diepoxide(perfluoro-1,2-epoxy-13,14-epoxy-4,11-dioxatetradecane) in 30 grams ofliquid HFP at -40° C. was added to the reactor over a period of 2 hours.The reactor was maintained at -34° C. for 24 hours. The polymer wasisolated by removing the HFP diluent under vacuum at -34° C. andallowing the polymer to warm slowly to room temperature. The polymermass was protected by a dry nitrogen atmosphere. The inherent viscosityof the polymer in Freon® E-3 at 30° C. was 0.16 dl/g corresponding to anumber average molecular weight of 75,000. Freon® E-3 is2H-heptadecafluoro-5,8-bis(trifluoromethyl)-3,6,9-trioxadodecane.

EXAMPLE 10 Heat Treatment and Vulcanization of Poly-HexafluoropropyleneOxide Containing Nitrile Cure Site

The polymer prepared as in Example 9 was heat treated at 140° C./6.7 Pafor one hour, giving a partially gelled polymer. The polymer was washedwith water on a wash mill for 20 minutes at room temperature and wasthen dried under nitrogen at 75° C./2.67 kPa for 2 days. Then 41 g ofthe polymer was milled at room temperature on a roll mill with 1.24 g (3parts per hundred rubber) of micronized tetraphenyl tin and 6.2 g (15phr) of SAF carbon black predried under nitrogen 120° C./2.67 kPa. Thecompound was dried at 92° C./2.67 kPa for 3.5 hours, and 5.5 g portionswere compression molded in a 63×18×1.5 mm steel mold at 210° C. and 17MPa for 2 hours. The cured slabs were removed from the mold at roomtemperature and were then post cured under nitrogen according to thefollowing schedule:

    ______________________________________                                               70° → 204°                                                         6 hrs                                                               @204°                                                                           18 hrs                                                               204° → 288°                                                        6 hrs                                                               @288°                                                                           18 hrs                                                               @315°                                                                           48 hrs                                                        ______________________________________                                    

Stress-strain properties of a typical vulcanizate at room temperatureat:

    ______________________________________                                        100% modulus, MPa  1.0                                                        Tensile-at-break, MPa                                                                            4.6                                                        Elongation-at-break, %                                                                           250                                                        Permanent Set, %   4                                                          Hardness, Shore A  30                                                         ______________________________________                                    

O-rings prepared by compression molding and post-curing the compoundunder the above conditions but without the final post-curing at 315° hadcompression set (ASTM D395-78, Method B) at room temperature/70 hoursapproximately zero percent and at 204°/70 hours approximately 40percent.

We claim:
 1. A homopolymer of a perfluoroglycidylether of the formula##STR33## wherein R_(F) is: ##STR34## wherein R¹ is a carbon-carbon bondor a linear or branched perfluoroalkylene group of 1 to 12 carbon atoms;##STR35## Y and Y' are --F or --CF₃, provided that only one of Y and Y'can be --CF₃ ; or ##STR36## wherein R³ is a linear or branchedperfluoroalkylene group of carbon content such that the moiety ##STR37##does not exceed 15 carbon atoms; Y, independently, is --F or --CF₃ ; nis 1 to 4; and Q is as defined above.
 2. A copolymer of aperfluoroglycidyl ether of the formula ##STR38## wherein R_(F) is:##STR39## wherein R¹ is a carbon-carbon bond or a linear or branchedperfluoroalkylene group of 1 to 12 carbon atoms; ##STR40## Y and Y' are--F or --CF₃, provided that only one of Y and Y' can be --CF₃ ; or##STR41## wherein R³ is a linear or branched perfluoroalkylene group ofcarbon content such that the moiety ##STR42## does not exceed 15 carbonatoms; Y, independently, is --F or --CF₃ ; n is 1 to 4; and Q is asdefined above and at least one comonomer selected from the groupconsisting of hexafluoropropylene oxide, tetrafluoroethylene oxide, adifferent perfluoroglycidyl ether from the class of perfluoroglycidylethers described above and a perfluoroglycidyl ether of the formula##STR43## wherein R¹ is: ##STR44## wherein R¹ is a carbon-carbon bond ora linear or branched perfluoroalkylene group of 1 to 12 carbon atoms; Q¹is --SO₂ F, --COF, --F, --Cl, --Br, --I, --CN, --CO₂ H, --OC₆ F₅, or--CO₂ R⁴ where R⁴ is --CH₃ or --C₂ H₅ ; Y and Y' are --F or --CF₃,provided that only one of Y and Y' can be --CF₃ ; or(ii) --CF(R²)₂wherein R² is --F, --CF₂ Cl, --CF₂ CN, --CF₂ COF, --CF₂ CO₂ H, --CF₂OCF(CF₃)₂ or --CF₂ CO₂ R⁴ where R⁴ is defined as above; or ##STR45##wherein R³ is a linear or branched perfluoroalkylene group of carboncontent such that the moiety ##STR46## does not exceed 15 carbon atoms;Y independently is --F or --CF₃ ; n is 1 to 4; l and Q¹ is as definedabove; or (iv) --C₆ F₅.
 3. A copolymer of claim 2 in which the comonomeris hexafluoropropylene oxide.
 4. A copolymer of a perfluorodiglycidylether of claim 1 and a polymer selected from the group consisting ofhomopolymers of hexafluoropropylene oxide, homopolymers oftetrafluoroethylene oxide, and copolymers of at least two ofhexafluoropropylene oxide, tetrafluoroethylene oxide andperfluoroglycidyl ethers of the formula: ##STR47## wherein R_(F) ¹ is:##STR48## wherein R¹ is a carbon-carbon bond or a linear or branchedperfluoroalkylene group of 1 to 12 carbon atoms; Q¹ is --SO₂ F, --COF,--F, --Cl, --Br, --I, --CN, --CO₂ H, --OC₆ F₅, or --CO₂ R⁴ where R⁴ is--CH₃ or --C₂ H₅ ; Y and Y' are --F or --CF₃, provided that only one ofY and Y' can be --CF₃ ; or(ii) --CF(R²)₂ wherein R² is --F, --CF₂ Cl,--CF₂ CN, --CF₂ COF, --CF₂ CO₂ H, --CF₂ OCF(CF₃)₂ or --CF₂ CO₂ R⁴ whereR⁴ is defined as above; or ##STR49## wherein R³ is a linear or branchedperfluoroalkylene group of carbon content such that the moiety ##STR50##does not exceed 15 carbon atoms; Y independently is --F or --CF₃ ; n is1 to 4; and Q¹ is as defined above; or (iv) --C₆ F₅.
 5. A copolymer of aperfluorodiglycidyl ether of claim 1 and a polymer selected from thegroup consisting of homopolymers of hexafluoropropylene oxide andcopolymers of hexafluoropropylene oxide and perfluoroglycidyl ethers ofthe formula: ##STR51## wherein R_(F) ¹ is: ##STR52## wherein R¹ is acarbon-carbon bond or a linear or branched perfluoroalkylene group of 1to 12 carbon atoms; Q¹ is --SO₂ F, --COF, --F, --Cl, --Br, --I, --CN,--CO₂ H, --OC₆ F₅, or --CO₂ R⁴ where R⁴ is --CH₃ or --C₂ H₅ ; Y and Y'are --F or --CF₃, provided that only one of Y and Y' can be --CF₃ ;or(ii) --CF(R²)₂ wherein R² is --F, --CF₂ Cl, --CF₂ CN, --CF₂ COF, --CF₂CO₂ H, --CF₂ OCF(CF₃)₂ or --CF₂ CO₂ R⁴ where R⁴ is defined as above; or##STR53## wherein R³ is a linear or branched perfluoroalkylene group ofcarbon content such that the moiety ##STR54## does not exceed 15 carbonatoms; Y independently is --F or --CF₃ ; n is 1 to 4; and Q¹ is asdefined above; or (iv) --C₆ F₅.
 6. A copolymer of a perfluorodiglycidylether of claim 1 and a copolymer of hexafluoropropylene oxide andperfluoro-6,7-epoxy-4-oxaheptanenitrile.
 7. The copolymer of claim 6 inwhich the perfluorodiglycidyl ether of claim 1 isperfluoro-1,2-epoxy-13,14-epoxy-4,11-dioxatetradecane.
 8. The copolymerof claim 6 wherein the perfluorodiglycidyl ether of claim 1 isperfluoro-1,2-epoxy-15,16-epoxy-6,11-dimethyl-4,7,10,13-tetraoxahexadecane9. A vulcanized article made from a copolymer of claim 4.